The deployment will use 3-C nodes from multiple owners, including the PASSCAL-owned 3-C nodes if possible, in order to study volcanic-tectonic and long-period upper crustal earthquakes beneath Mount St. Helens (MSH). Upper crustal long period earthquakes were identified with vertical component node data from 2014 but they are difficult to locate accurately or characterize with only vertical components and no recordings in or near the summit crater. About 100 nodes will be deployed in the summit crater and northern breach to provide near vertical coverage of the local earthquakes, and an additional ~100 nodes will be deployed in a ring around MSH near tree-line. The summit crater deployment will be conducted in coordination with the USGS CVO scientists Wes Thelen and Seth Moran. The nodes will be deployed in August 2017 immediately after the IAVCEI conference in Portland so there is little flexibility in the start time. Once deployed the nodes will record continuously for ~30 days to take advantage of the full battery life to record as many earthquakes as possible. Deployment and recovery fieldwork should be completed in 2 days each.